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arXiv · 1411.7702

Optical microscope and tapered fiber coupling apparatus for a dilution refrigerator

A. J. R. MacDonald·G. G. Popowich·B. D. Hauer·P. H. Kim·A. Fredrick·X. Rojas·P. Doolin·J. P. Davis
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Abstract

We have developed a system for tapered fiber measurements of optomechanical resonators inside a dilution refrigerator, which is compatible with both on- and off-chip devices. Our apparatus features full three-dimensional control of the taper-resonator coupling conditions enabling critical coupling, with an overall fiber transmission efficiency of up to 70%. Notably, our design incorporates an optical microscope system consisting of a coherent bundle of 37,000 optical fibers for real-time imaging of the experiment at a resolution of $\sim$1 $μ$m. We present cryogenic optical and optomechanical measurements of resonators coupled to tapered fibers at temperatures as low as 9 mK.

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A. J. R. MacDonald, G. G. Popowich, B. D. Hauer, P. H. Kim, A. Fredrick, X. Rojas, P. Doolin, J. P. Davis. 2014-11-27. Optical microscope and tapered fiber coupling apparatus for a dilution refrigerator. https://doi.org/10.1063/1.4905682

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